The printed circuit board (PCB) maker JLCPCB is the first board house to offer full-color printing on the silkscreen layer for made to order boards. 

Meant as a boon to designers creating colorful or cute PCBs, there are uses for this technology that transcend circuit board use.

Many Makers have used circuit board design for artistic purposes. Your author has done so in three previous Adafruit guides:

• Making PCB Jewelry & Art with Gingerbread and KiCad
• Making Wearable Badge Art with Printed Circuit Boards
• LCARS-inspired Circuit Board Panel

With this new capability, the color possibilities are opened up compared to standard PCB colors represented by the substrate, copper, silkscreen and solder mask. Any design an artist wishes to be placed on a thin, hard surface can be made easily at a fairly low cost.

This guide will show you how I used JLCPCB to make some colorful jewelry as an example. You may replicate the project with the included files. Hopefully also you'll glean how to make other designs with the process.

Borrowing liberally from Wikipedia here, Piet Mondrian (1872-1944) was a Dutch painter and art theoretician who is regarded as one of the greatest artists of the 20th century. He is known for a pioneer of 20th-century abstract art, as he changed his artistic direction from figurative painting to an increasingly abstract style, until he reached a point where his artistic vocabulary was reduced to simple geometric elements.

When World War I ended in 1918, Mondrian returned to France, where he would remain until 1938. Immersed in post-war Paris culture of artistic innovation, he flourished and fully embraced the art of pure abstraction for the rest of his life. Mondrian began producing grid-based paintings in late 1919, and in 1920, the style for which he came to be renowned began to appear.

Yves Saint Laurent's Mondrian Fashion Collection

The Mondrian Collection was designed by French fashion designer Yves Saint Laurent (1936–2008) in 1965. This collection was a homage to the work of several modernist artists. Part of this collection were six cocktail dresses that were inspired by the paintings of Piet Mondrian. Because these six shift dresses played a major role in this collection, the collection is called the Mondrian Collection.

The Mondrian collection was widely published in many fashion magazines, with one dress featuring on the cover of Vogue in 1965. Mondrian style dresses became very popular, with many mass manufacturers producing copies of the designs for lower prices, which were then widely circulated.

Today

The designs migrated from dresses to other forms of fashion. Today, the colors within black lines may be found in a full range of fashion and decor items.

My previous PCB work had included floppy disk earrings and a pendant. These were nostalgic and practical, as they could be represented by three colors and fashionably nostalgic (many folks like vintage computing). Affordability is also a factor as PCB costs are by the square inch and board houses usually make a minimum number per order, usually 3 to 5.

I decided to make another earring and pendant set for this guide. Thinking color, I chose the bright colors and black borders of Mondrian design. A good proof of concept which will not break the bank.

Deciding on Your Own Design

With the choice of colors, it opens the design possibilities. The constraint is still that designs will be printed on an inflexible 1.6mm substrate with white silkscreen (think of white as the canvas layer). The board specification choices are more limited than with full range PCB services at present.

Size

Think of the design you want and the functionality of the object produced. Do you want some drink coasters with a logo on them? Perhaps a pendant of a favorite pet?

Choose the picture to use and think of the size of the creation, keeping in mind that the larger it is, the more expensive it will be when you order.

Resolution

Like all printing endeavors, the resolution of the image you plan to use can make the final product look better. The JLCPCB PCB printer is 1200 dots per inch (472.4 dots per cm), 6 color. Having an image with a high number of pixels per inch/cm is recommended.

Colors

Looking at the PCBs on the Overview page and above, representing a range of colors appears easy to do. The image I chose has simple primary colors, only because I decided on that design.

You are free to use as many colors as you wish, noting that inkjet style printers may have limits, and subtle color changes may be made in manufacturing. Picking colors that do not need exact matching (like not using specific Pantone colors) is recommended.

Open your favorite image creation or drawing program on your computer. If you are limited to a browser, you might try the Online Image Editor or similar (though I have not used it in my example). For Windows, I am a fan of Paint.Net.

I grabbed a ruler to decide how wide and long I wanted my design. I chose 0.5x1.0 inches roughly which I refined to 12.7 mm x 29.21 mm through the design process.

You don't want to make things too big if not necessary to save money. 

Set the image dots per inch or equivalent fairly high to have a good resolution printed on the 1200dpi printer.

Draw Your Design

Draw your design in the image editor. I suggest starting with a outline of how big the item will be and what shape it will take.

I made a rounded rectangle in black and made the corners not in the outline transparent. I then made black lines in the rectangle in the style of Mondrian. Finally I filled some of the rectangles with color. Rather easy for my design.

You may wish to import a bitmap from somewhere else: a school or team logo, or a pet's picture. It's your choice (just be careful of image licensing issues). In my case, Mondrian's paintings are older than 75 years and mine are "Mondrian inspired," so they are doubly ok.

When you think the design is done, save it in PNG (bitmap) or SVG (vector) format, the formats that EasyEDA Pro supports for color PCBs.

Getting Fancy: Having Copper Show Through

My original goal was to have the yellow not be printed but have that be the golden color of ENIG, the gold plated copper that is the only finish JLCPCB allows for exposed copper. To prepare your bitmap for this, use the erase function in your image editor to make the copper part transparent also.

It doesn't come through, but the upper left and lower right boxes have been changed from yellow to transparent in the PNG file.

Going in to the design process, I was ready to fire up KiCad. Then a full stop. The JLCPCB announcement page links to designing a PCB with JLCPCB's EasyEDA Pro software. Sigh, another program to learn. They have a version which can be downloaded onto a computer and a web application. I chose the web app and found it capable enough for my needs, although there seemed to be a few gotchas in the process.

Do refer to the guide linked above for the company details.

"At present, our production process exclusively supports Gerber files featuring colored silkscreen layers that have been exported from EasyEDA Pro."

There are selections in the EasyEDA Pro software allowing importation, use and exportation of color bitmap files, so their software is the only one to support this process at present.

Importing from Other PCB Programs

I did not try to design the basics of the board in KiCad (for example) and then attempt to import that into EasyEDA Pro for the PNG file. This approach might be possible. 

As noted, I chose the EasyEDA Pro web app, and I used Google Chrome. EasyEDA Pro recommends Chrome or Firefox with hardware acceleration. Incognito mode should not be used.

The downloadable version works on Windows, Linux, and Mac.

Enable Silkscreen Printing

To begin, activate the "Use JLCPCB Color Silkscreen Process" option in the PCB settings:

Settings icon – PCB / Footprint – General – Using JLC color silkscreen technology

Import Your Design

EasyEDA Pro supports importing color images via the Top Menu: Place – Image. PNG and SVG vector image files are supported. In the Import dialog, tick the option to place the image in its original quality. 

The image will automatically be placed on the top silkscreen layer, but you can move it to the document layer or the bottom silkscreen layer if needed.

For my design, I imported the image into both the top and bottom silkscreen as they were identical.

If your design is single sided, place it on the top silkscreen.

Create Your Board Outline

You can make the circuit board/PCB outline one of two ways:

1. Use the image you imported to guide the board outline shape.
2. Make a board outline using your image file dimensions and move the graphics to fit that board outline.

While I used option two, the board outline was simple for the earrings. For a complex shape like a pet, you might do better to trace the outline. 

A circular logo is fine. A dog's tail may be too much of a sliver/point to fabricate, as examples. Reading the guidelines, 2mm appears to be the smallest milled size so all PCB features should be at least 2mm.

Why is a board outline needed?

For artwork, there likely is not an associated schematic, so there is no way for the software to estimate the board size. 

Also, likely you want the outline to match your image design and size desired.

Drawing the Board Outline

Select the Board Outline Layer (11) on the right. If you don't see it, select View (V) - Right Side Panel. You can quickly switch between layers at the bottom also.

Use the Board Outline Tool to draw your outline. The options aren't numerous: Rectangle, Circle, and Polygon. Polygon would be used for a complex shape like tracing a picture.

My design is a rounded rectangle. A rectangle can be changed in the Property tab shown above.

The corner radius for my design turned out to be 2 millimeters for a nice rounded rectangle. I highly recommend rounded corners for art PCBs so the user doesn't get a stick/poke from a sharp corner.

Make sure the height and width match your image height and width from your drawing program, unless you plan to have a border around the image, in which case the size would be larger. My design has no border, though the previous NASA logo project required a circular border to cover the points exposed on the NASA "Meatball" logo.

Previewing The Design

In the Top Menu: View – 2D/3D Preview, you can preview the color silkscreen and images. I suggest previewing to ensure you are getting the design you want.

You must set Silkscreen Technology to Colorful Silkscreen in the right-side Attributes panel to see the effect of color printing (below).

For my design, Ladyada challenged me to make the yellow portions copper colored rather than printed yellow. 

The JLCPCB process only offers ENIG coated, which means exposed copper will have a very thin gold plating. Gold seemed good!

I edited my bitmap to make the yellow squares transparent and specified that silkscreen should not be in those areas.

I thought I put in the copper layer but after two rounds with JLCPCB engineers, apparently the Gerber file did not have the front and back copper layers. Drat.

As the unexposed areas will be silkscreened, specifying the whole copper layer as copper should be fine. For a two sided design, be sure to put copper on the front copper and back copper layers.

Select the Copper Pour tool shown above. Draw a box around your design. You then specify the copper pour name and which layer you want it on.

Removing the Solder Mask to Expose the Copper

Setting parts of your PNG to transparent prevents printing, but you'll need the solder mask removed to see the copper. 

Click on the Top or Bottom Solder Mask layer at the right and then draw a filled region with the tool to the right of the Copper pour tool.

Seeing the Bare FR4 board

As I made a mistake and did not put in the copper pour but did remove the solder mask, my two areas did not have copper but showed the yellowish FR4 base board. Yikes.

But it worked out as I was looking for a yellow color and the board is yellow(ish). Note that the ordering process says a black board - that is not what I received.

Also in 3D and 2D views, the removal of the solder mask looks like the copper layer is visible. This is deceiving as this is the FR4 substrate.

When everything is done, the next step is to save your work in the special Gerber files needed by the JLCPCB process (this is why we can only use EasyEDA Pro as it has the capability to add the color file information).

Open the Top Menu and select Export – PCB Fabrication File (Gerber).

Tick the Silkscreen option to export color silkscreen and then export the Gerber files.

After exporting the Gerber, the Gerber zip file will include files specifically for JLCPCB multi-color silkscreen.

My Gerber Files

If you'd like to make the Mondrian boards I made (complete with FR4 for yellow instead of ENIG), the files are here:

This step is optional. But it is one I wish I had done to catch the lack of copper layer on my boards.

I don't find the JLCPCB Gerber viewing capability as flexible as I found KiCad. So if you'd like "a second opinion", look for a 3rd party browser-based Gerber file viewer.

Whichever viewer you chose, it will not show the extra color printing on the silkscreen. Just overlook this detail and focus on the layers.

For a design printing color on the silkscreen not showing copper or FR4, you can likely skip this step.

If you are looking to view the copper and lack of silkscreen, I used the PCBWay viewer here.

The key to a viewer is the ability to toggle layers to ensure the design for various PCB elements is to your board layout. If something is missing or amiss, you can tell.

If all looks ok, it is time to order!

You can place an order directly in EasyEDA, or uploading Gerber files generated from EasyEDA on JLCPCB's quote page.

If you are using a saved Gerber file, click the Add Gerber file.

You need to set the corresponding options in the JLCPCB ordering system to select multi-color silkscreen. If you don't use their settings, it can cause delays or incorrect boards.

Multi-color silkscreen currently requires the following PCB specifications：

See the image above showing these settings.

Likely 2 layers would be correct and there is likely no vias in art designs so whatever results in no cost should be used.

IMPORTANT: Advanced Settings

This tripped me up. The "Advanced Options" below the board information didn't show anything! You MUST expand the section yourself with the "v" in the upper right of that section (circled in green), making it a ^.

Now select the settings above ensuring you click "EasyEDA multi-color silkscreen" under Silkscreen Technology.

If you fail to select this, you will not get the color printing you want.

Save to Cart

Now focus on the order details in the upper right portion of the page (I "circled" it in orange). The required ENIG finish adds cost if there is bare copper. Don't check Build Time, as there is no parts assembly on these boards.

Ordering

Go to your cart and select the PCB you just made. The standard order is for 5 copies and that should be good to get them in hand to be sure they are exactly what you want.

Select shipping. This will likely be more than the boards cost. It is just the way it is when the only service that does this process is in China.

Pay and complete the order. Relax and Wait.

Review and Status

JLCPCB engineers review all designs to ensure they meet the company's design rules. Any perceived issues and they will contact you per the information you provide on ordering.

You can return to your JLCPCB user page and check on orders to see the status of the board at the various manufacturing steps. 

Likewise they will provide shipping information per the service you checked. If the service offers tracking, you may use the tracking number to follow the shipping process.

I received the boards back in decent time, as I selected DHL shipping for my address in the US. I was disappointed in the lack of ENIG copper due to the error, but the yellow of the FR4 was decent and the translucency actually adds to the look.

The finish looks good with a slight sheen. It does not scratch off with a fingernail. To ensure extra durability, you can look to put a final finish on the items, but for my purposes their finish appears to be adequate.

The jewelry hardware may be found at your local craft store or online in many places. I used:

• Two earring hooks
• Four split rings
• One length of chain
• One magnetic clasp

Using two pairs of small needle nose pliers, I carefully opened the split rings, added the earring hooks and the boards and closed up the split rings. For the pendant, it uses two split rings and a chain is put through. A clasp is added at the chain ends. The chain length is selected to fit where you want the pendant to fall.

And here I am wearing my new jewelry. I hope you enjoy making your own as much as I enjoyed making and wearing mine.